Train-dispatching system for railroads



March 3, 1931. w. w. WENHoLz TRAIN DISPATCHING SYSTEM FOR RAILRQADS Filed June l5, 1929 U .miv m93 Ild miveao u. ||l l null new mm. in. .Teig im T115.. ...EN N N A Gm ,Y I 2T||| w u A \N.v` u CDT.

one Where the synchronous selectors are normally at rest and are operated onlyfor/a few revolutions in response to each lever movement and each change in track circuit .occu- Y pancy. .The batteries 16 and 17 have been illustrated forconventional purposes, and instead ot connectingthe Wires of the system to theplus terminal (B+) kand theminus terminal (B-) of these batteries, the reterence characters B+ and B- havebeen Vapplied to those parts of the Wiring systemV which are connected to these battery terminals, this inorder to siinpli'ty the Wiring arrangement and facilitating comprehension of i theV circuit arrangement. vIt is believed that the nature otthe'system ilustrated embodying the present invention, as Well as its operating characteristics, are best understood by considering'the operation thereof, and for tliisreason the operation of the system'will now be taken up. i

tpcrazofaLet us lirst assume that the lever assumest its normal vneutral position in Ywhich position only the contact L engages a Ilstationary Contact. Let us also assume that `the arms A and A1' are rotated in synchronisni. Under the condition assumed the relays AR and BR in the dispatchers oflicehave their lower windings energized repeatedly once for each cycle of operation ot' the arm A. These circuits may be traced as follows hey :nning at the terminalB ot' the battery 1G, the lower Winding ot the relays AR and lll?. in nuiltiple, trom Whencethese circuits are the same'and constitute, Wire20, bacl contact 2l ot theV indicating relay 1R, wire 22, Contact segment 2? of the arni A, Wire 2l to common return uiire C connected to the midpoint o'l' battery 1G. Since the relays AR and BR are direct current polar relays of the permanent magnet stick type, the armatures thereof Will not beV physiciallymoved, but they will merely remain in their letthand position, as shown. Nothing will transpire at the Way station at the east4 end otl the passing siding P S, with the arms A and A1 inY position tWo,because`the contact 58 oi relaylZ is open, so that We` may proceed toassu le other conditions of trailic and positions or thelever L. Y y y Y Let usassumerthatthelever L is'moyed to its right-hand position, signifying east bound traliic. Under the condition assumed 'liefcircuits or'the botto1n"windings of reaysiilt and BR are again momentarily completed atthe second step in the operation of the synchronous selectors, and a local circuit is completed at the dispatchers oiiice when the rotating arm A. assumes a position to contactV with the stationary contact 8. This circuit may be traced as follows: beginning at the terminal B -i, contact 25 of the lever L, Wire 26, upper Winding of the relay AR, Wire 27, contact 28 oi' the lever L, Wires 29 and 30, contact segment 23 of the arm A, Wire 31, to common return VWire C. The circuit justsage wire 15, arm A1 and contact 3 of the synchronous selector at the Way station, Wire 39, liront contact`40 ot' the track relay T, wires all' and lVl2bacl: contact @t3 ot the control relay Z', Wires all and 45, the Winding of the relay Y and-the upper Winding of the relay X in multiple, Wire "-16, to common return Wire C connected to the midpoint ot' battery 16.

ltfshould be noted that there is a multiple.

branch inthe circuit just traced, including the switchbox contact 13 in 'multiple with the back contact 13 oi' the relay Z, bot-h contacts it which' are now closed.

`The completion of this circuit supplies current to operate the relay BR and the relays Xand Y to their right-hand position.v Since the relays AR and BR in the dispatchers othce now'both assume the right-hand position the indicating relay 1R will remain deenergized and since these relays AR and BR operate simultaneously the audible signal BL is not sounded. Also, With the relaysX and Y operated to Atheir right-hand position simultaneously the control relay Z is energized to itsright-hand position vthrough the following circuit-z-beginning atthe {crininal B+,gcontact 48 of the relay Y, Wires 49 and 50,. Winding ofthe control relay Z, Wire 5l',`contact 52 of the relay X, to the terminalB- of the batte-ry 17. vThe control relay Z` is thus operated to its right-hand pesi-tion in response to operation of the lever L to its right-hand position. lilith the polar contact in the right-hainl position and the neutral contact Viu its raised position, the east bound signal L "l or ED 'may be cleared, providingl trl nc Yconditions in' advanceare favorable, anddepending upon the position ot' the track switch' S. i

Letus 'now observe the .operation of the' systemA as Vthe synchronous selector arms A and A1l continue to operate without any lil() by y.the arrows, Iit is ,noted that these armsjust before completing. an 4entire revolution engage the stationary contacts 2. At this point/,in the ,rotationof the contact arm A, there-lays Al vand BR are both operated to the leit, but-,they only-remain there momen-- tarily beoa-.usethey areretmjned to the righthandj position, for reasons vheretofore -eX- plained, when the LContact arm A assumes the third position and engages the contact 3.

At `the distant ,Way` station, however, one of the relays X and Y, vnan'ielythe relay X, is returned to its lett-hand posi-tion when the arm A1 assumes itssecond position in engagement withfthe Vstationfrry contact 2. The circuit Yfor operating `the relay X to the leftlia-nd position is completed when the arm A1 assumes a` position to engage the Contact 2, and maybe traced as follows-:-beginning at the terminal iB lconta-ct 1 -8 ofthe rela-ys Y assuming its rightfhand position, wires 49 and, 57,' lfront Contact.'58.01c the relay v ZY `assuming its attracted position, Wire 59, hottom winding of the'relay X, Wire 60, contact segment '6l oi theaun A1, Wire 62, to common return Wire C eomiectedto the midpoint of Ahattei-'y 17. The completion of this Circuit will retfu-rnrthe rela-y X to aposition opposite tot-hat .Which-it previously occupied, this because {theQcontact 48 of the rel-ay Y -still assumes .the position to which it .was

previouslyoperated. vlith thesrelays X and Y ont of correspondence, namely, the .relay Y` assuming,l theright-'hand position and the relay X assumi-ngthe let-'hand-.positiom the terminal B+ connected yto both terminals ot fthe'controlrelayZ., so thatfthe control relay'Z. is de-energized, but byfreason of `its slow-acting vchara-cteristics remains in its energizedposition a moment longer, and if the 4relays 'X and Yl are Vagain operatedto corresponding` .positions .when the arm A1 reaches the third position, in enga-gement with thecontact'l, the relay'xZ willnot actually l assume its' tlc-energized. position.-

yVVhenthe rotatingarm A1 reachesthe third position, niengagei'nent with the stationary contact 3,- the circuits forthe relays X and Y, heretofore traced, area'gain completed, with the exception that the current `passes .only

through t-he switchloox contact 13 instead of passingthroug-h the contacts "123 and ,43 `in multiple, as was ylieretoiforethe cese, thereby operating` the rel-aysX yand Ytotheir. rig-ht.

hand; position. .Since the relay Y still assumes jits right-hand position, 'its armature is not aetuallyfmoyed,brit the relay X, Which has ,been operated to its leftlhand position in the meantime, is .again lretin'ned to its llehtfhand position, thereby reap-pinne energy to the control relay ofthe same poefty :heretofore @replied there minieme-g.

the-lciitrol relay Z :energized: 111 S110-@Mbenoted. that .the .denventiolal ell-Owing 0f the 'neutral position and With'the `lever L in its righthandposition. Let us now assumethat the disp'igcher Wishesito place all ofthe signals EM, ED, WM vand WD .at the east end QneSSine:Sidineljfattopfand eerder-t0 do so moves 'hisjleverL lto :the ,middle neutral p.osit ,ion.` VVith the 4lever rL .moved tothe neutral ,position the Irelays AR- and BR .in

the .dispatchers Office 1viillbe returned tok their .left-.hand lpositiontheneXt time the @21.11A engages the Asifitioliirifolitzict .2., ,and

fro

ifelilain .there for reasons,` heretofore plained, namely hecansenoenerzcgy` can be apf pliedito .their upper windings.

vLet us now, howeyer, observe what takes plee@ at the ivsystationfin thetthe-0'rut heretefore tra-Ced .over 39.1.1.6 r#hilf-d l channel" n- @hiding the contacts?) and the; message vWire, 1.5,11Qiviqpen-.at the-Contact@ ofthe lever L. "lflien-.the rotatingl Contact A1 reaches the second position, n'engagement with the contactgthe relay isreturnedto the lefthand position. through the in ediiim of. the closurepf a circuit .throngh its bottom winding of relay. X andV heretofore traced, .and 21S the .sentant arm A1. reaches-'the third P0: Sten engagement with the Contact '3 .nething transpires atthis Way Statiomsothatthe telers X-end .Y'thereatr feminin the PQ- Siiienehonn in the drawings., Causing the relay `Z toassnrne its (ie-energized position and.; openingfthe signal. circuit at .the lneutral contact, ofthecontrol relayz. .It isthiis annali-erit-menthesinglemessge-GrcuitmenvQllQd. iS capable of `onergfirinct'r, the relay yZ` tofeither of its polerpositions land .is alsoy capable of de-energizing the polar-neutral controlzrelayZ.

SYS-tem lwhenzth Contiellverifl1-isiiioied vt0 itslefhend,Positionpresumablybeweert@ dispatcher .Wishes iv-est phound trahie to move .over the switch S at the .eastend of the Vpassto their left-hand.positionsvforj reasons herel toforegiven, huts'nCetheSe relays ,AR and alreadyassnme the `left-hand 4pSitioi-i theirarmatnres are not moved.. :Upon eneagement 0f the arm A .Witt-1th@ stetenery .Contact 3 the following Circuit .ferth imperi ,Letfnsznow fhserve,the'flinctioninglof the Winding vof ythe :relay BR is completed:- beginning at the terminal B+ of the battery 16, Wire 35', upper Winding of the relay Y BR, Wire 36,'contact 37 of the lever L in its lett-hand position, Wires 65 and 30, contact segment 23 ot the arm A, Wire 31, to common return Wire C connected to the midpoint of battery 16. The closure of the circuit just i traced operates the relay BR to the right-hand position, bnt simultaneously with the closure of 'the circuitust traced a circuit is closed for the upper Winding of the relay AR, which operates theI relay AR to the right-hand' posiy tion. lThis latter circuit may be traced as i Vfollows:--beg:,rinning at the'terminal B- of i station, Wire-,'39, Contact 10 of the Itrack relay T, Wires L11 and 42,bacli Contact 13.01? the relay Z, Wires lland L'15,vvinding o1!` therelay Y and'upper Winding ot the relayX in multiple'-, Wire 46, to common return Wire C con'.

nected to the midpoint of battery 16. The' completion of this circuit operates the relaysV AR, rand Y to the lett-handfposition. y Since the relays AR and BR now both assume the left-hand position, the indicating relay IR'remains cle-energized. `With the relays X and Yl assuming the left-hand p0- sitio'n' the control relay Z is energized to its let-hand'position through the circuit here- CTI tofor'e traced, except that the contacts 48`and 520i the relays Y and X respectively now assume the let-handfpositionp lVith the polar Contact 55 in its left-hand position and the neutral contact 56v of thecontrol relay Z closedthe West bound signal WMV OriyyD- depending` .upon Whether the switch S is in the main track or Athe take-siding position, is permitted to clear, providing trame conditions in advance of these signalsVV are favorable. Y

We have now considered the operation ol the system in vso Jfar as rthe controlof the control relay'Zby the lever L is concerned. lnv other Words, We have considered energil zation of the control relay Z to its right-hand energized position', to its lett-handy energized position, and also the manner in Which this relay Z isde-'energized upon movement of the lever'*L to its' neutralV position. It is'now believed expedient to observe the functioning1 ofthe system in responseto the passage of a train over the detector track circuit.`

YVehave just assumed that the control relay' Zv is energized toits lett-hand position in responserto the'lever L to its lett-hand position. Let'us `further assume that thetracl; switch S isV in its main track position and that 'or this yto the midpoint of the battery 16.

vvise have been completed at the third position of the synchronous selectors, has nonT been breiten at contact et() of the track relay i. This breaking ot the message circuit at the contact i-O will ot course-effect de-energization ot the control relay Z, but this is ot little importance in that the signal il/'M is directly pnt to stop in response to dropping ot the track relay T, by circuits not specifically showin bn.u illustrated in the 'li/light application r-er. No. 120,423 heretofore referred to, so that de-energization ot' the control relay Z n ay be tolerated, it being inconsistent to have any one oil the signals at proceed While the track relay Tis de-energized.

@peni .r ot' the Contact 46 of the track relay T hoivever produces an eiiect upon the apparatus in the dispatchers of'rice,'and mani'li s to the dispatcher that this track relay T has been tlc-energized; For reasons heretot'ore explained the engagement of the contact segment L33 with suitable stationary contacts vvnile the arm A engages the contact 2, completes energizing circuits for the bottom Winding of the relays AR and BR. thereby operating both ot these relays AR and BR to their lett-hand position. Also with the message circuit intact at the way sta tion vthe relays AR and BR are operated to their right-hand pos.ition. It on the other hand the contin t arm A assumes the third position in engagement With the stationaryY` Contact 3 With-the message circuit heretofore traced not completed in its entirety, because the contact l() of the track relay T is included therewith andthis contact l() is now assuming'its retracted position, it readily appears that the relay AR will remain in its left-ha nd position. The relay BH, however, will be operated to its right-hand position upon coinpletion of the following circuit begiijining at the terminal B+ of the battery 16, wires upper Winding ofthe relay BB, wire 36, Contact 37 of the lever L in its left-hand position, Wires 65 and )6,fcontactrsegment Wire 31, to common return wire C connected y The completion or' this circuit operates the relay BR to the right-hand position, and since the relay Alt has not been operated to its righthand position, because the contact et() of the track relay T .was open, thelrelays VAR and BR are new out of correspondence, thereby ejll'ecting enero' ation of the indicating relay llt throu.G toe following vcircuitzhbeginning the tern1inall3+, contact 68 of relay in its right-hand position, Wire 69, Wind-4 .is slight-ly rslowdropping,

.Contact 3.

ving of the indicating relay R, Wire; 70, con

tact 7 l vof' the relay viiR'ini-ts left-handposition, to the common return Wire C connected to the midpoint oi: batt-cry 1G. Y i

lilith. the' indicating relay 11R energized,

`the hitting otthecontact Q1 Vbre:iksjftl-iecircuits for energizing the bottom windiiigslof .the relays AR andfllt, so that their condition of energization'irfill not be changed when 'the contact arm A again. assumes' the .second position during its rotation. Lifting ot'the contact .74 of the 4rela;7 IR. rhowever,Y after lirst momentarily sounding th'e'bell BL, conipletes the circuit.` for4 energizing lthe indicatinglamp IL, .which circuit ana-y hetraced as follows z-beginning at the` tern'iinal' B+,

Wire 75, contact 76 ofthe relay AB assuming the relay BR assuming the right-hand position, -TWire 7 9, contact 7.4 ofthe rel ay IR lin its `raisedposition, Wire 80, indicating lamp 1L, -Wii'e 81 to common return Wire@ connectedto t'henmidpointof batte-ry 16.

Continuation' lot' the operation ofthe 4synchronous selector system, irrespecti've .ot

. 40,-the circuit licieto-fore;tra:ced for the/upper Winding oi the relay AR Aand rnclndirigthe message Wire 15 'is completed, .thereby causing Vthe relays AR- vand BRto assunieoorre- Vspending positions and therehyfetfecting deenergization `of the indicating relay ,IR-.and

y eXt-inguishment of the'indicatinglanipIL.

y The system described thns enableswtherdispatcher to transmitA three distinctive control conditions over the Imessage f channel `coin'- ipleted at the third Contact in its-.cycle-'ot 'operations-and in `addition toaiiordiiigtliesethree dis Ainc-tire cffvntrols-`the 'systenifatords the transni issioii. of an. O Sindication oyeri'tlie saine message channel this through thefinedinin oitnieans at. 4the ldispaitchems oiiicc for Adetectiligt-h'e [continuit-y ot theanessage. channel zduriiigthe .instant :such message chan-nel should he conipleted,and this ability to detect theicontinuity ofthe message circuitenab'lesan OS indication, which "can onlyreirist when the control .relay .,-Z :may ;-be lde-'energiz'ed, 4to V,be transmitted.. ln other Words, sincerthe occupancyot the detector trackcircuitiitseltputsthe signals WM, and

to sto'p,;thereis vno need 'ot having ccntlie clearing;A

trol relay-Zenergized, as iai' as the control -oftliese signalsfis concerned, and Vfor this reason the -ffrontfcontact 40 of the detector track relay T may be included in series with the message circuit controlling the relay Z;

reason ni'ayboth loe carriedon overthe saineVv message circuit. s

itis-'ofcourse understood that each of the various-contactlpoi'nts, or steps in the synchronous cselector system, Will afford the sanie'fnuinber-of lniche-"ations as already de.

scribed lin 'connection -With.Contact point Also, yit isto Ibejunderstood thatvthe switch S may 'be operatedV by a switch machine 'controlled over 'anotherchannel of the synclirono'us yselectorsystennand itthis is the..n 'case the. operation Yoffthe switch machine is indicatediby the switch box Contact 13 associated With the 'switch S. In this connection it should' he'noted that ythis yswitch box contact 13 is in inultiplewitih the back Contact 43 ofthe coirtrolrelay Z, s0 that the contact v13 iniistlbe-closed Whilethe'controlling relay kisenergized vto vavoid yde-energization of this control '-relfay during the' Jfollowing cycle of ope'rationl of thesynchronous selectorsystem. il f Inforder 'toimore clearly understandthis feature .offthe circuit arrangement, let us assuine-'thatthe switch box-contacts 13 are opened,#possibly because of misadjustment o'j the switch S. 'Iiithisconneotion the control relayZ maybepickedup,in that this relay '.Z'is controlledby't'he relays. X and Y, and the relays 'X` and Yniay receive ktheir control lthroughfthe'back 'contact 43 of the relay Z.

As soon, however, 'als-'t'hevrelay .Zassinnes its energizedpositionthe message circuit is opened-at th'eback Contact 43 (contacts 13 being'opened) seth-at during the'neX't cycle of operation the relays XandY'Will be operated to their normal position and Will eii'ect deenergization ofthe'conti'ol relay Z. In' the -ti'iird-cycle of operation the contfol relay Z is Yagain,picked-np', and it-is againcle-energized during lthe ffourth .cycle 'of operation.`

In other Words, the 'indicating lamp "IL will be iashed 'in' accordan ce with this V:operation of the -coiitrolrelay and Will-indicate to `the dispatcher-that the track switch is in an 'intermediateposition. It should heunderstood that, if desiiedftlhe'back contact`43 may he entirely'oni'ittcd, in which event the failure of closure of contact 13 `Will result in illuminating'indicating .lamp'f'l'L and 'in .holding the-signals associatedwith the switch Sai; stop.- Also, if the siizitch S isoperated by a switch machine, this operation of the switch machine is indicatedthroi'igh'the medi-um of contacts 13. Fnvrtherit suchswitch machine is^eniplcyed, .since .as .just V-lcrought ont `the dispatcher has intermittent control 'over the relay Z, that is, may operate this relay Z to either of its polar positions even though con- Y a certain control position during the completion ofsuch message channel, so that these relays are reconditioned once during each operation oi' the synchronous selector system. Also, since tivo such polar permanent magnet stiel: relays are used -in the dispatchers oilice in connection with a particular message channel it is possible to determine whether such message channelis actually completed in the field or not, and this feature may be taken advantage of and used for the purpose of transmitting OS indications from a Way station to the dispatchers oi'ice.

Having thus shown and described one rather speeiiie embodiment of the present invention, as applied toa synchronous selector system Which hasbeen conventionally shown, it is desired to be understood that the particular embodiment of the present invention illustrated has been selected for the purpose of ,facilitating description of the underlying .principles ofthe invention and its operating characteristics and has not been selected for the purpose of showing the scope of the invention or the exact circuit arrangenient preterably employed in practicing the same, and that various changes, modifications, and additions may be made to adapt the invention to the particular problem encountered in practicing the same, all Without departing Yfrom the spirit or scope of the invention of the idea of means underlying the same, except as demanded by the scope o'l the following claims. i

lVhat I claim as new is i l. In a train dispatching system of the synchronous selector type; the combination 4with a selector .system includinga message channel rendered available momentarily onceduring each cycle oi' operation of such system, a dispatchers otiice at one end of said message channel, and a Way Astat-ion at the other end of said message channel; a polar-neutral relay at said way station; and means for controlling said relay to assume either of its energized positions or its de-energized position in'response tothe polarity of current or the absence of current transmitted over said n'iessage channel comprising, two-polar relays having stick characteristics both energized to a particular polar po'sition'in response to c urrent of corresponding polarity transmitted oi-er said message circuit51means for operatthe position assumed by said polar relays;

whereby said polar neutral relay Will assume one energized position if said polar relays both assume one polar position, assume another energized position if both polar relays assume the other polar position and assumeV a cle-energized position if said polar relay-s assume positions out of correspondence.

Q. In a train dispatching system ofthe synchronous selector type; the combination with a selector system includingr a message channel s rendered available momentarily once during cach cycle of operation of such system, a dispatchers oflice at one end of said message channel, and a Way station at the other end of said message channel; a ].iolarneutral relay at said Way station; and means for controllingV said relay to assume either of its energized positions or its cle-energized position in response to the polarity of current or the absence of current transmitted over said message channel comprising, means for establishing a local energizing circuit for said polar-neutral relay including a direct current source of one polarity, for establishing a local. energizing circuit for said polar-neutral relay including a direct current source of the reverse polarity and for breaking the last made circuit'in response to the transmission of current of one polarity or the the other polarity over said message circuit or in transmitting no current over said message circuit.

8. In a traindispatching system of the synchronous selector type; the combination with a selector system including a message channel rendered available momentarily once during each cyclel of operation of such system, a dispatchers oiiice at one end of said message channel, and a Way station at the other end of said message channel, a lever at the dispatchers office indi-eating means at the dispatchers ollice, electro-responsive control means at said Way station, means for controlling said electro-responsive means in responso to a change of the position off said lever and lover said message channel, and means for controlling said indicating means responsive to the continuity of said message channel during the time said message channel is available for use.`

4. In a train dispatching system of the synchronous selector type the combination with a selec-torsystem including a message channel rendered available momentarily once during each cycle of operation'ot such system, a dispatchers olriceat one end of said message channel, anda Way station at the other end of said message channell a lever v`at the dis- -patchers oijiice, indicating means at the dispatchers VAoffice, Y electro-responsive `control means 'at said way station, means for controllll!) i Si) Cil ling saidelectro-responsiiie means -inf response to a vchange of the position of said lever and over said message channel, and meansgfor controlling said indicating means including a relay ot the snap-action type included in said messagecliannel.

lna'train dispatching system of the-[synchronous selector type; the combinati'oirivith a selector system including a message channel'j rendered ava-ilabl i momentarily once during each cycle of operation ofA su'cli system, a dispatchers oilice at one end of said message channel, awaystfation at the other end of Isaid n'iessage'channel, a lever at Athe dispatchei"s oiiice indicating means at the dispatchers otfice, electro-responsive control means at lsaid Way stati'omnieans for controlling said electro-responsive means in responseto a change of the position 'ot saidlever and over said message channel, and means for controlling said indicating means in accordance Witlrthe continuity oiisaid message circuit during the time said message channel is available including two polar relays of the snap-action stick type, one oi' Which assumes an abnormal position if potential is applied. to the message ciricuit and the other of which assumes an abnorf mal position if current ilows over said message circuit, saidindicating means assuming` 0 its' indicating conditionii2 sai'dfpolar relays are out of correspondence. c a' train dispatching system oit the synchronous selectortype; the combination With a 'selector system including a message channel rendered' available moinentarilv once duringv eacli cycle of operation otl suoli system,l a dispatchers office at one end ot said message channel, a Way station at the other end ot said message channel, a lever at the dispatchers O oilice,vindicating means atthe dispatchers oiiice, electro-respmisive controlineans at said waystation, means for controlling said electro-responsive means in response to a change of the position of said lever and over said D message channel, and means for controlling said indicating means inclndin a plurality ot devices which assume corresponding positions vif current flows in the message circuit and potential is applied to the message circuitbut which assume noncorresponding positions if potential is applied to but no current flows in said message circuit. l

7. In atrain dispatching system of the syn* chronous selector type; the combination with a selector system including a message channel rendered available momentarily once during each cycle of operation of such system, a dispatchers oiiice at one end of said message channeh and a Way station at the other end of said message channel; a lever at the dispatchers oiiice indicating` means at the dispatclieris oice; electro-responsive control means at said way station; means tor controlling said electro-responsive means 1n responseto al change '13 of the position of said lever and over said teni, the coinbin r1 particular point in ,which alniessave sage circuit, which renders said indicating 'ii-ie" current loivs 1n' said message circuit.

active ii; potential is applied and no 8. 'ln Aa selector system of the type in'fWliicl-i a message circuit may be momentarilyceinpleted by the application otstepping iinpnlses to a stepping line, the combination with a message circuit connecting' acentral o feaiida distant Way statiom ot means loying the saine message circuit for trans- Aconnecting said central oiiice and ,raid Way stations,- oi' a l particular messagel circuit 'in- "luding said message Wire, a tnoiviosition in ,icating relay energized to be operated to particular"position during' a particular inipnlse in a cycle applied to said onel circuit providii-ig an indieating` contact in said pai'- ticular me cirouitis closed, and means 'lor operating said relay to thefopposite position atan eail" i n, time of'sai i,- particulfar impulse, 'win-mc 'I said relay assumes one position'- substantially continuously if said indicating contact is closed and assumes the opposite position continuously it said indicating Contact is closed.

l0. In a lcentralized tiaiic controlling sys- `ation With a message Wire connecting 'afee l 'oilic'e and a distant way station7 seiector means located partly aft said central oii Yte and partly at said way station and operable through acycle oi oper: t" n at isc'losed includinga contact at said l i 1' +o", 4- t ,M251 7 sgi-1+, oince anc a conm a saimay at tivo-positionrelay at said central olii e include-d in said message ci'i` uit-With aso'uice ci'iliifent' toloperate s relay'toa particularposition upon closure 'of said circi indicating Contact 'in said' message circuit said A ay l'station 'to event suchi opeil'aH of of said hreifafz andothe'r nieanstor opera 'saidi-elay toits opposite' position at a 'pointk in such cyclej'us't preceding sare particwli'rr point, whereby saidrelay substantially coiitimoesiy "assainesafp-@sinon cc'iiespmii ting a controland i'ece'ving an indication .s

saidv said central oiiice over sailmomeny when an indication f ier time in sncli' cycle tllvn `to Whether said indicating Contact' is open or closed. u I I 11. In a centralized traIic controlling system, the combination with a message Wire connecting a central oiiice and a distant way station, selector means located partly at said centra-l oiiice and partly at said Yway station and operable through a cycle of operation at a particular point in which .a message circuit is closed including a contact at said central oiiice and a contact at said way station, a two-position relay at said central oiiice included in said message circuit with a source of current to operate said relay to a particular position upon closure of said circuit, an indieating contact in said message circuit at said vay station to prevent such operation of said relay, and other means for operating said relay to its opposite position.

12. In a centralized traffic controlling system, the combination with a message wire connecting a. central office and a distant Way station, selector means located partly at said central oiiice and partly at said way station and operable through a cycle of operation at a particular point in which a message cir cuit is closed including a contact at said central oflice and a contact at said way station, a twoposition relay at said central olice included in said message circuit with a source of current to operate said relay to a particular position upon closure of said circuit, an indicating contact in said message circuit at said way station to prevent such operation of said relay, a traliic controlling device at said Way station, means for control'- ling said traiiic controllingdevice over said message circuit, and other means for operating said relay to its opposite position at a point in such cycle just preceding said pau ticular point, whereby said relay substantially continuously assumes a position corresponding to Whether said indicating contact is open or closed. Y

13. In a centralized traiiic controlling system, the combination with a message wire connecting a central oilice and a distant way station, selector means located partly at said central office and partly atsaid Way station and operable through a cycle of operation at a particular point in, which a message circuit is closed including a contact at said central oiice and a contact at'said way station, a. two-position relay at said central oiice included in said message circuit with a source of current to operate said relay to a particular position upon closure offsaid circuit, an indicating contact in said message circuit at said Way station to prevent such operation of said relay, a tralic controlling device at said way station, means for controlling said traffic controlling device over said message circuit, and other means for operating said relay to its opposite position. Y

14. The' method for substantially continuously indicating whether or not aV Contact is closed located at the remote end of an intermittently rendered available circuit, which resides in operating a. two-position relay to a particular position when said circuit is available and said Contact is closed, and in operatingsaid two-position relay to the opposite position a moment before each instant said circuit is rendered available.

15. Means for substantially continuously indicating Whether or not a contact is closedV located at the remote end of an intermittently renderedavadable circuit comprlsing, a twoposition relay and a source of current in said circuit for operating said relay to a particular position each time said circuit is rendered available and said contact is closed, and other means for operating said relay to the opposite position just before said circuit is rendered available.

17. Means for substantially continuously indicating Whetheror not a contact is closed located at the remote end of an intermittently rendered available circuit comprising, a. two

position relay and a source of current at the local cnd in said circuit tor operating said relay to a particular position each time said circuit is rendered available and said contact is closed, and other means for operating said relay to the opposite position just before said circuit is rendered available.

In testimony whereof I affix my signature.

WALTER W. VVEN HOLZ.

DISCLAIMER 1,794,563.Walter W. Wenholz, Rochester, N. Y. TRAIN-DISPATCHING SYSTEM FOR RAILRoADs. Patent dated March 3, 1931. Disclaimer iiled February 16, 1934, by the assignee, General Railway Signal Company.

Hereby enters this disclaimer to claims 3 and 4 of said Letters Patent, which are in the following Words, to Wit:

3. In a train dispatching system of the synchronous selector type; the combination With a selector system including a message channel rendered available momentarily once during each cycle of operation of such system, a dispatchers oi'lice at one end of said message channel, and a way station at the other end oi said message channel, a lever at the dispatchers office indicating means at the dispatchers oHice, electro-responsive control means at said Way station, means for controlling said electro-responsive means in response to a change of the position of said lever and over l said message channel, and means for controlling saidindicating means responsive to the continuity of said message channel during the time said message channel is available for use.

4, In a train dispatching system of the synchronous selector type; the combination with a selector system including a message channel rendered available momentarily once during each cycle of operation of such system, a dispatchers oflice at one end of said message channel, and a Way station at the other end of said message channel a lever at the dispatchers office, indicating means at the dispatchers office, electro-responsive control means at said Way station, means for controlling said electroresponsive means in response to a change of the position of said lever and over said message channel, and means for controlling said indicating means including a relay of the snap-action type included in said message channel.

[Oficial Gazette March 13, 1934.] 

